Docker is an excellent containerisation system ideally suited to production servers. It allows you to do one small thing but do it well. For example, breaking a large blog up into individually maintained containers for a web-server, a database and (say) a wordpress instance. However due to inherent security woes, Docker doesn’t play nicely with multi-tenanted machines, the kind which are the bread and butter for researchers and HPC users. That’s where Singularity steps in.
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Molecular dynamics analysis in MDAnalysis
Any opportunity to use rigorously tested and supported analysis tools rather than in-house code is, in my opinion, an opportunity you owe it to yourself to explore.
My preferred tool for analyzing the output of molecular dynamics (MD) simulations is MDAnalysis, a Python library that provides robust and easy-to-use tools for analyzing most common files output by MD packages (including PDB, DCD, COR, and XTC file formats). But, of course, MDAnalysis can analyze any PDB file, not just one output from an MD simulations. There may be an opportunity in your workflow to incorporate MDAnalysis to save time or to provide more robust error handling than whatever in-house code you currently use.
The address of a gene
Most scientists working in the biological sciences or an overlapping field have encountered various ways of identifying genes and proteins. There are many different types of identifiers. For example, searching for the PDB ID: 2IW3 (which represents elongation factor 3 in yeast strain S288C) on UniProt gives us a results column labeled “Gene names” that includes no less than six (!) ways to refer to the gene that produces this particular protein. This can be frustrating – it is easy to get into trouble when you think you have a consistent gene naming scheme when you do not, especially if you want to cross-reference gene lists.
You’re getting on my biscuits
Jaffa cakes are God’s own snacks and I will brook no opposition. I don’t mind if they’re McVitie’s brand Jaffa cakes, or Pim’s, the suspicious European variety. Even Sainsbury’s Basics Jaffa cakes float my balloon. Take a soft sponge base, slap some jam and chocolate on that puppy, and you’re golden.
But if you describe your love of these glorious creations, the conversation takes a familiar turn. Are they cakes or are they biscuits? it goes. HMRC tried to classify them as cakes – or was it biscuits? Something like that. It had to do with VAT…
Continue readingA few more reasons why UNIX is awesome
One could easily find dozens of reasons for which UNIX — mainly Ubuntu — is simply, the best operating system. Although I remember people in my proximity mentioning this for ages, it’s been only a few months that I’ve realized what are the true advantages. Helpful for this were all the people teaching/demonstrating in various modules during my first year in SABS/DTC: quite often we would be asked to do something in the console rather than by clicking the mouse. In the meanwhile, I’d wonder why using the console can be better from a nice, user-friendly GUI (i.e. Windows…). Tools like sed, grep, tar and of course alias-ing form a quick answer. I will not argue more about these but demonstrate two more tools/tricks.
Continue readingPython Handout
Many OPIGlets extensively use Jupyter (in either Notebook or Lab flavour) to prototype and present their work. However, as project progress frequently notebooks are converted into regular python files for a number of reasons, losing the notebook functionality.
Wouldn’t it be nice if we could combine some of the benefits of Jupyter notebooks (not least the ability to present both code & results naturally) with regular python files?
Enter Python Handout.
Python Handout was recently (5th August 2019) released by Danijar Hafner and allows Python scripts to be converted into handouts with Markdown comments and inline figures (see above picture).
Installation is via pip (pip3 install -U handout) and Python Handout supports python 3 scripts.
While I’ve not used Handout much (yet), I will definitely be experimenting more in the coming weeks.
How to Iterate in PyMOL
Sometimes pointing-and-clicking just doesn’t cut it. With PyMOL’s built-in Python interpreter, repetitive actions are made simple.
Continue readingConstrained Embedding with RDKit
This blog post explores the RDKit function ConstrainedEmbed.
Continue readingA gentle primer on quantum annealing
If you have done any computational work, you must have spent some time waiting for your program to run. As an undergraduate, I expected computational biology to be all fun and games: idyllic hours passing time while the computer works hard to deliver results… well, very different from the more typical frenetically staring at the computer, wishing the program would run faster. But there is more — there are some problems that are so intrinsically expensive that, even if you had access to all the computers on Earth, it would take more than your lifetime to solve a slightly non-trivial case of them. Some examples are full configuration interaction calculations in quantum chemistry, factorisation of prime numbers, optimal planning, and a long, long, etcetera. Continue reading
Some useful tools
For my blog post this week, I thought I would share, as the title suggests, a small collection of tools and packages that I found to make my work a bit easier over the last few months (mainly python based). I might add to this list as I find new tools that I think deserve a shout-out.
Biopandas
Reading in .pdb files for processing and writing your own parser (while being a good exercise to familiarize yourself with the format) is a pain and clutters your code with boilerplate.
Luckily for us, Sebastian Raschka has written a neat package called biopandas [1] which enables quick I/O of .pdb files via the pandas DataFrame class.
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